Research on a Novel Driving Strategy of BLDCM Based on Continuous Three-phase Current Mode

• 1、School of Automation, Northwestern Polytechnical University, Xi’an 710072
• 2、AVIC Computing Technique Research Institute, Xi’an 710065

Abstract：Aiming at the problem of inactive phase and non-commutation current ripple of brushless DC motor (BLDCM) working with the conventional two-conduction mode, which made power density lower and torque ripple more of BLDCM, a novel continuous three-phase current driving mode for BLDCM was proposed in this paper. The novel driving mode was conducted by taking the torque equation and back EMF equation as the constraints to obtain the current extremum for minimum copper loss, partitioning the position of rotor as twelve sectors, and finally according to sector sequence, the extremum was distributed as the command of three-phase current in the inner current loop. According to the sum of three phase current of Y-connected winding BLDCM was zero, the continuous current output of three phases was implemented by the current closed-loop control of two phases. In order to verify the feasibility and effectiveness of the novel driving mode, both the Simulink simulation model and experiment condition were established. The simulation and experiment results validated that the novel driving mode was used to restrain the torque ripple, minimize copper loss of BLDCM.

Keywords： Brushless DC motor(BLDCM) Continuous three-phase current Current-limited solution Torque ripple reduction